Yumeko Jabami is the main protagonist of Kakegurui. She is a transfer student at Hyakkaou Private Academy and the classmate of Ryota Suzui and Mary Saotome. Yumeko's family is aligned with the family of Kirari Momobami and challenges her for Hyakkaou Private Academy.
Yumeko is a very attractive pale-skinned girl with a large bust. She has long black hair that is styled in a hime-cut and brown eyes, along with two curved streaks at the side of her face. In the anime and manga, her eyes are sometimes seen glowing red whenever she becomes excited. She wears the standard female Hyakkaou Private Academy issued uniform; a red blazer with black trim lining the cuffs and collar, a white button-up dress shirt, a dark pleated skirt, a tie and black/grey colored stockings. As well as the academy's issued footwear, brown colored loafers with black soles. She also sports red lipstick, red painted fingernails (sometimes seen as pink) and a ring around her left thumb.
Yumeko is shown to be a very upbeat and charismatic character who consistently attracts the affection or interest people around her. Not only is she able to befriend those who previously disliked her, she is able to catch the attention of the entire student body. She does just that on her very first day of school and manages to continue doing so on nearly a daily basis. Every time she notices an opponent cheating in games, her button gets switched to a bloodthirsty side of her, usually seen when her eyes turn red and she frightens her opponents.
Though she is typically very friendly, she abstains from acting this way when she uses her perceptiveness to expose her classmates' cheating. She is capable of doing this even after only a couple of rounds of gambling, as she is easily able to decipher what strategies and tricks they are using to skew the game in their favor. While doing this, she may unabashedly condemn the other player and their ways, preferring honesty over politeness in such cases.Despite the disadvantage she faces when others cheat, she does not concede. This is largely due to the fact that she does not seem to experience fear or anxiety from taking risks. In fact, it gives her a thrill. Because of this, she tends to take high-risk bets in gambles, even if she has nothing to rely on but luck. Though this can sometimes end in her loss, she is emotionally unaffected by the results; she simply uses her loss or gains a means to further indulge her gambling habit.
She seems to be fairly aware of her eccentricities and that her way of gambling doesn't follow normal conduct. As such she rejoices when people support her or encourage her, especially those close to her, greatly valuing their friendship, albeit in her own ways. She rationally understands that her behavior is immoral as she confesses to feel guilt for not feeling guilt over the people she has ruined through gambling.
When climbing the stairs in the Tower of Doors, she mentions that she has very little stamina.
Kakegurui - Compulsive Gambler
Yumeko transfers to Hyakkaou Private Academy and is shown around the school by her classmate Ryota Suzui. Ryota tells her about the school which she seems to be interested in. She became popular in her class as she is surrounded by her fellow male classmates. She is then challenged by Mary Saotome to a gambling match which she accepts. She is shown to be losing after betting the match after betting one million yen during the first two rounds. Yumeko then asks Mary for another round to which Mary agrees, when asked how much she's willing to bet, Yumeko reaches into her school bag and produces stacks of yen that amount to 10 million, especially when Yumeko puts 10 million yen on one round. Yumeko then points out that Mary rigged the game in her favor by having 21 out of 30 students place rigged cards that would tip the game in her favor. Yumeko reveals that she noticed this patterns from the beginning and reveals Mary's strategy to her. Yumeko wins the gambling match leaving Mary with a debt of 8.8 million yen which she tells Mary that her debt is already paid as their gambling match proved to be a fun ordeal. After that, Yumeko leaves her classroom were Ryota calls out to her. He asks her how she knew about Mary's rigging of the match to which she reveals to him how she deduced everything. She later gives him money to pay his debt that he has to Mary as thanks.
The next day it is seen that Yumeko and Ryota are now friends. They enter their classroom to find Mary's desk vandalized with the entire class smiling menacingly. Mary blames it on Yumeko because of her loss yesterday before lurking away to earn the money back. Ryota takes Yumeko to the cafeteria where he explains the oppressive structure of the school, the student council, and their gambling prowess, increasing her already growing love and excitement towards the school. Yumeko is then invited to play Double Concentration against Itsuki Sumeragi. Yumeko plays a close game but loses the 20 million yen given as a trial. Yumeko demands a rematch and Itsuki accepts under the condition that should Yumeko lose, Itsuki can remove her fingernails and toenails to add to her nail collection. Yumeko realizes her opponent was cheating and wins on the very first turn by remembering every card's patterns on the back. While Itsuki is in shock, Yumeko confronts her on the cheating and starts spewing out her excitement mixed with anger asking for another game where they both bet their nails. The confrontation caused Itsuki to cry and decline Yumeko's desire making the latter disappointed.She then is curious in the other Council members and heads to the Traditional Culture Club to face off against Yuriko Nishinotouin. There she sees Mary lose against her, making her debt even bigger. Yumeko then gambles against Yuriko and quickly catches on how she cheats and what a terrible person she is. Kirari Momobami even enters the scene and wants to watch. But due to Yuriko's luck, Yumeko loses and becomes a housepet. The next day, some girls make fun of her and call her mittens. But Yumeko then starts to act like a cat and purrs, which freaks the others out. She doesn't mind being a housepet, especially since she has the rights for an official match.
The next day, Yumeko is approached by Jun Kiwatari and his friends, where they command her to strip for them, but she refuses since they're far from her type. Jun gets angry and wants to get violent, but Midari Ikishima steps in and scares him away. Yumeko thanks her and Ryota is also relieved. Soon after the student council holds a special game for housepets, where they can reduce their debt. Yumeko shows up there and is in the same group as Mary. Mary is still angry at her as they also play against Jun and Nanami Tsubomi. The two come up with a plan to trick him. They wrote down a false debt and switched their boards when no one was looking. During the Indian poker game, Yumeko also noticed how Nanami and Jun were cheating. But, she told Sayaka Igarashi that she wanted to continue playing, without reporting the cheat. Yumeko also tries to convince Nanami to stand up to Jun and tells her that she has to defend herself. In the end she and Mary reveal their twist and they won. Jun is furious and tries to attack her, but Sayaka electrocutes him down. They meet up with Ryota and Yumeko hugs Mary and wants to be friends with her. She acts somewhat clingy, which makes Mary uncomfortable.
The next day, the Student Council was told by Sayaka, that Yumeko actually has a sister. She is apparently hospitalized and Yumeko is paying all of the costs, meaning she must be incredibly wealthy. Yumeko was then planning to challenge Kirari to an official match, but on their way Midari shows up and arrests them. Midari then plays a dangerous game against her, because she wants to get shot by Yumeko. Yumeko trusts Ryota to act as the dealer during the game and gives him a hint on how they could trick Midari. Yumeko already realized that Midari was going to purposefully lose so that she will get shot by her. Yumeko exposes that fact and states how much she hates people who gamble only for a certain outcome. She leaves with Ryota with Midari behind them as she cries.
When she meets Ryota watching a video, she learns about the idol Yumemi Yumemite, who is also a Student Council member. Soon after she is challenged to a game by her. They meet up in Yumemi's dressing room. Yumemi acts very sweet and cute but Yumeko sees through her facade. Because earlier she found a threatening letter addressed to Yumemi in a trash can. That accusation makes Yumemi angry and starts to show her true colors. But then Yumeko reveals that she has planted a recording device on Yumemi's manager. She says that if she wins their game she will publish that recording, since she hopes that will make the game more exciting for both of them.
When the live on-stage gamble starts both of them have to sing something. That is Yumemi's specialty and although Yumeko sings good, she shouldn't have won. But she did win, because Yumemi did that on purpose. Yumeko quickly sees through that but plays along silently. She realizes exactly when Yumemi plans to win and when to lose. When it came down to guessing the birthday of an audience member the dice landed on Mary. Yumeko didn't know her birthday just like Yumemi and simply guessed June. She was closer than Yumemi and thus won the entire game. Yumemi was angry, but accepted that Yumeko would play the recording. But her fans still didn't give up on her and cheered Yumemi on. Yumeko then announces however that she found a letter, that seemingly tried to sabotage Yumemi's career. The accused is Kaede Manyuda. He comes down to the stage in order to settle the uproar. Yumeko then wanted to gamble with him. Since he refused, she was forced to use her official match right. Then Kaede had no choice but to accept.
At first they think that they cant even play without a dealer, but the vice-president steps in and says she will act as such. They play Choice Poker. Yumeko bets a lot of money and gets very thrilled throughout the game. But eventually she asks Itsuki to help her, since she states she's running out of money. Itsuki comes down and helps her out but the bets go higher and higher. Yumeko prompts Itsuki to bet her life and gets gambling crazy. Itsuki gets determined and takes the risk. Kaede wants to intervene, since such a high sum isn't fair. But then the vice-president takes off her mask to reveal its actually Kirari. Everyone is shocked. Kirari then allows them to continue the game. Kaede is also forced to bet his own life's worth. Yumeko and Itsuki actually planned this together in order for that outcome. In the end Yumeko wins and Kaede is devastated. While his unconscious body is transported away, Kirari talks with Yumeko. They find out how much they agree about things and they want to play a game together. And both of them plan to bet everything they have.The game Kirari chose is called Tarot Cards of Fate. Three people will draw a card, which is them and Ryota. He doesn't want to take so much responsibility, but Yumeko is excited. The stakes for the game are that whoever loses will have to leave the school. That means Yumeko wouldn't be able to gamble anymore which would mean she lost everything. She then draws the first card. It is only worth 1. While Kirari decides, she talks to Yumeko about the existence of fate. Yumeko is very intrigued by that. When Kirari draws a -21 card, Yumeko doesn't really react. Since Ryota now has to draw a card, he is extremely nervous. Yumeko tries to calm him down, by saying only she can lose. He notices a mark on one of the cards, which could be the instant win card. The others tell him to take it, but he is unable to take that risk. So he announces that he wants to draw a random card. Hearing that from "her Ryota", immediately gets her very excited. She takes his hand and tells him to take the ultimate risk. So he draws one and its +20. The total score is 0, which means the game ended in a tie. Yumeko looks forward to playing again with Kirari and states, that since fate wanted both of them to stay, life must have something very exciting in store for them. When Kirari calls Ryota and Mary subjects, Yumeko denies that and states that she has found the best possible friends that she could ask for.
Yumeko is very excited about the election and all the gambling she can do. She is also intrigued by the thought that distant relatives of her have arrived at the school. Mary Saotome and Ryota Suzui tries to warn her and tell her that they are the Momobamis who come to battle against Kirari Momobami. But Yumeko is happy as long as she gets to gamble. They are called by Rei Batsubami and tells them that they have been invited to a game that Erimi Mushibami prepared involves a guillotine. Yumeko is very thrilled about this. But she will have to play with Midari Ikishima, who she still dislikes. During the game, she shows no fear when cutting the threads. Before the game she noticed that the table was missing a stopper, so she asked the observer to remove them. When she again asked Inaho Yamato during the game, if she had removed them, Erimi though that she meant the plate protecting their fingers from actually being cut off. Erimi began to hesitate and started to cry, so Yumeko and Midari both shouted at her to continue. When it came down to only two strings, Midari cut them both at once. Erimi pulled out her finger and so Yumeko won. But she was extremely angry at Midari for taking away that 50/50 chance in the end. She then thanks Erimi for the great game.
The next day, they are again invited to a gamble this time by Miyo Inbami and Miri Yobami. When they meet, Miyo hugs her and they both say how nice it is to finally meet. Runa is also overseeing the game, since she doesn't trust the Momobami sisters. They are playing Nim Type Zero and Yumeko also begged Ryota to play. She enjoys the game, but halfway through she starts feeling sick. She has to lay down on a couch. It turns out that Miyo poisoned Yumeko while hugging her. Under the effect of that poison, she starts to lose conscience. Mary steps in to take her place and Yumeko then quickly tells Ryota to trust in Mary. They manage to win and then bring and treat Yumeko to a hospital, along with Rei's help.
When Yumemi Yumemite wants to get more votes, she approaches Yumeko and wants to gamble with her. But, an unexpectedly guest named Kawaru Natari, who is secretly one of the Momobamis as her real identity is Sumika Warakubami, steps in and in turn challenges them to a game. Yumeko and Yumemi sing together on stage. She didn't know about the audience being bribed however, since she wouldn't have liked that. When they still lose the first round, Yumeko is excited and asks Yumemi what they should do now. Yumemi is annoyed because she is surrounded by weirdos. In the second round, both Yumemite and Natari must taste a spicy macaroon. Kawaru correctly guesses which one was Yumemi's spicy one. Yumeko counted how often Kawaru chewed with each macaroon and was able to eliminate A, since she chewed the most there. And then she randomly picked B, which was correct. While Runa Yomozuki was preparing the third round, Yumemi talked about how she felt inspired and wanted to be defeated by her greatest idol. But Yumeko didn't like that Yumemi was going to have fun without her. She dislikes people who give up so easily. So in the third round she didn't cooperate with Yumemi at all and always truthfully said which card she drew. But after some motivation from her fans, Yumemi got some faith back. Yumeko believed she was acting the whole time and was impressed, but Yumemi quickly told her that her struggle was real. But Yumeko was still content with her gaining back faith and went along with Yumemi, which resulted in Kawaru's loss and their win.
After that game, Yumeko quickly contacted Terano Totobami and wanted to play the Greater Good Game. She chose Itsuki Sumeragi and Kaede Manyuda as players, while Terano chose Ibara Obami and Miroslava Honebami. She is excited to play the game. Rumia Uru explains the rules and the first people go to spend their coins. While that happens, Kaede asks Yumeko whether she ever feels any remorse when destroying an opponent. She replies, that she only feels remorse for not feeling remorse. Rei gets extremely angered by her coldness and mentions her hospitalized sister. Yumeko simply replies by asking her if she ever saw anyone fall into despair, to which she retreats. When Itsuki returns, Yumeko excitedly asks her if it was fun. After the results of the first round are announced, they realize there must be a traitor. As the discussion becomes more heated, Yumeko is sure something exciting will happen. She then has the idea to write down a number for each player and that amount they must pay. That way they can estimate how many traiters there are and maybe even who. But there still seemed to be two traitors. Kaede then pointed the finger at Yumeko. She didn't deny it and went to him, telling him that they should do it together. Then they both reveal themselves as the traitors and that they will pay zero coins. That was just a trick in order to get the others to pay, which worked out. At the end of the next round, Kaede then figured out that the true traitors are Miroslava and Itsuki. Everyone agreed to expel Miroslava and the game was then over. Yumeko managed to win 16 votes. When Itsuki's bet with Terano was revealed, Yumeko declared it simple self-perception. But she knew it was for the best. Then, Itsuki officially retires from the election.
The next day there was a broadcast going on. During the broadcast, Yumeko challenged Kirari to a game in front of a live camera. But, Sayaka Igarashi rushed in and calls Yumeko a pestilence to the school and wanted to bet everything with her. Kirari saw that opportunity and brought them to the Tower of Doors. She explains to them, how they must travel the tower. Yumeko is fascinated by the building. While Sayaka climbs down, Yumeko opens one of the outer doors. Since the moon wasn't visible from the door that it should be, she deduced that the entire tower was rotating with them. She arrived at the bottom later than Sayaka. She laughed at Yumeko for being so oblivious. But since she didn't know the Tower's secret, Yumeko was able to use the middle stairs and get all the way up. She won the game because she acts through curiosity and not simply through logic. Sayaka confesses her love for Kirari and jumps out. Kirari follows and they both land on a mattress. Yumeko watched and was very satisfied with the gamble. She thought about how one's feelings for someone else can never be outlawed.
When she and Ryota enter class, they find envelopes with invites to an auction. Yumeko attends of course and is excited. When going there, they meet Midari and Yuriko. Midari wants Ryota's help for getting Yumeko's attention back. But Yumeko coldly ignores her and acts as if she cant see anyone. Rei then greets them and the auction begins. Yumeko doesn't do that much at first. But through some clever put bets, she and Mary come to the conclusion that Rei Batsubami is also secretly participating. Rei promises to stop and Yumeko requests Inaho to bring the money she won from Kaede. Later they also deduce that there must be more players in another room. The election observers then bring in the 3 million Yen. She challenges Rei and wants to gamble with the real her. Rei agrees and drops her facade. The auction continues and everyone is stressed out, since Rei is only winning. But then Yumeko starts to instantly bet 101 votes. She continues to do that. Soon the others catch on. They all bet really low amounts and no one else intervenes. That way everyone won a lot and Rei is losing.
After she has no votes left, Yumeko reminds her that she still has the money. She states how she finds gambling fun, how she loves the moment when you risk everything. Rei realizes how crazy Yumeko is. When she was a child and peeked into the hospital room of Yumeko's sister, Yumeko was also there but didn't seem to worry about her sister but only interested in gambling. Rei accepts the gamble and wants to break the invisible chains of the Batsubami name. Yumeko stakes her name and Ririka Momobami comes on stage and suggests a coin flip, in which they agree as she flips the coin. Yumeko won and got the 3 million Yen back. But, Kirari was so impressed by Rei that Kirari took Rei back into the clan. Yumeko was seen gambling and losing all of her votes, in which she didn't mind though and was still enjoying it. She then sees Rei pass by in the hallway and Yumeko is happy for her as Rei became a new person.
Kakegurui - Compulsive Gambler
- A Girl named Yumeko Jabami
- Boring Girl
- The Slit-Eyed Girl
- The Girl Who Became a Pet
- The Girl Who Became Human
- Tempting Girl
- Refusing Girl
- Love-Dancing Girl
- Dreaming Girl
- Selecting Girl
- The Girl Who Bets Her Life
- The Girl Who Gambles Compulsively
- Gambling Girls Again
- The Girls of the Momobami Clan
- Do Not Touch this Girl
- Communicating Girls
- The Girl who Changes
- The Hollywood Star
- The Treacherous Girl
- The Winning Girl
- The Girl by her Side
- The Logical Girl
- The Girl who Bears the X
- The Null Girl
- The name Yumeko means "dream" (yume) "child" (ko).
- Yumeko's surname Jabami means "snake/serpent" or "hard drinker".
- The second kanji (喰）means to "eat" "drink" or "to receive a blow."
- In the first volume, it was revealed that Yumeko lives alone as her parents have passed away from unknown causes and she has an older sister who is currently being hospitalized.